Should tractors’ ergonomic evaluation index system in different life cycle stage be different? A delphi survey conducted in China

Abstract

In each life cycle stage of tractors, there are many differences in market circumstances, core technologies, user needs, operating requirements et al. Companies must develop different marketing and business strategies to be competitive in different life cycle stages, so do the strategies of ergonomic design and evaluation. In this paper, we proposed 3 hypotheses of tractors dynamic ergonomic evaluation and attempted to prove them in Delphi surveys. By analyzing the survey results made from 15 experts, full score ratio, mean and coefficient of variation were used to select the highly recommended indicators in each stage. At last, 3 different ergonomic evaluation index systems of each life cycle stage were established by Brainstorming and Delphi methods. The 3 different index systems showed that tractors dynamic ergonomic evaluation index system could be established by the method proposed in this study, and there should be some differences in tractors life cycle ergonomic evaluation strategies. The 3 index systems added with optional indicators for specific requirement can be applied to design, evaluate and optimize tractors in different life cycle stages.